But it is his stint as a trader in Bell Street Market in north London in the early 1970s - to fund his Masters in economics - that is mentioned most often.

"Let me underline that I'm certainly not seeking a part in EastEnders on the basis of this experience," he said.

"Surprisingly, the fact that actually I'm a professional economist comes across less frequently than the fact that I was once a stallholder. But there we go."

Radio 4 fan

Although not responsible for programme-making, Sir Michael said he was an "inveterate supporter" of BBC Radio 4, citing the Today programme, the Moral Maze and new comedy as his personal preferences.

And he is a fan of TV drama, naming ITV's Jane Austen adaptation Persuasion, the BBC's Life on Mars and US import The Sopranos among his favourites.

The latter "demonstrates we have something to learn from American television as well as offer to them", he said.

So what can we expect from his four years at the helm of the BBC Trust?

We must ensure that the decisions we take represent the interests of those who matter most - the public

Sir Michael Lyons

Setting out his position to reporters, he repeated the government's intention that the Trust would be the voice of licence fee payers.

"We must ensure that the decisions we take represent the interests of those who matter most," he said. "The public, the people who own the BBC."

That would involve safeguarding the BBC's independence and impartiality, he said, as well as ensuring the licence fee was invested wisely and listening to concerns from the commercial sector.

"And most of all, we will set a bold and exciting public service challenge to the BBC," he said.

A major survey is intended to help the Trust get in tune with the public

He would ask it to "draw on all its creative skills to provide the very best quality, most original programmes possible with the monies that are available".

The traditional BBC values of "inform, educate and entertain" were also central to his message.

And expanding on the idea that the Trust was the corporation's "parent body", Sir Michael pledged to be a firm but fair father figure.

A good parent "sets very clear expectations, is consistent in their behaviour, is supportive but is ready to question what they do", he said.

And he will have a lot of stern tests of his discipline and judgement when he takes the chair on 1 May.

His first priority, he said, was to learn what the public expects from the BBC - what they love and hate - which will include digesting the results of a major survey.

This insight will be used to rule on the executives' plans for spending the licence fee over the next six years - a decision that will be made in the next few months.

He also backed the proposal to move parts of the BBC to Manchester.

But he said it was too early to give a view on other specific decisions to be made in the coming months - such as approving the BBC's on-demand plans and approving adverts on the international parts of the BBC website.